Xu Dongyang, Chen Long, Dai Xing, Li Baoyu, Wang Yaxing, Liu Wei, Li Jie, Tao Yi, Wang Yanlong, Liu Yong, Peng Guowen, Zhou Ruhong, Chai Zhifang, Wang Shuao
School of Chemistry and Chemistry Engineering and School of Resource, Environmental and Safety Engineering, University of South China, 28 Chang'sheng Road, Hengyang 421001, P. R. China.
State Key Laboratory of Radiation Medicine and Protection, School of Radiological and Interdisciplinary Sciences (RAD-X), and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, 199 Ren'ai Road, Suzhou 215123, P. R. China.
ACS Appl Mater Interfaces. 2020 Apr 1;12(13):15288-15297. doi: 10.1021/acsami.0c01929. Epub 2020 Mar 17.
Contamination of TcO, a problematic radioactive anion in the nuclear fuel cycle, in groundwater has been observed in a series of legacy nuclear sites, representing a notable radiation hazard and environmental concern. The development of convenient, rapid, and sensitive detection methods is therefore critical for radioactivity control and remediation tasks. Traditional detection methods suffer from clear demerits of either the presence of large interference from coexisting radioactive species (e.g., radioactivity counting methods) or the requirement of extensive instrumentation and analysis procedure (e.g., mass spectrometry). Here, we constructed a luminescent iridium(III) organometallic complex (Ir(ppy)(bpy); ppy = 2-phenylpyridine, bpy = 2,2-bipyridine)-grafted porous aromatic framework (Ir-PAF) for the first time, which can be utilized for efficient, facile, and selective detection of trace ReO/TcO in aqueous solutions. Importantly, the luminescence intensity of Ir-PAF is greatly enhanced in the presence of ReO/TcO, giving rise to a distinct turn-on sensor with the detection limit of 556.9 μg/L. Such a superior detection capability originates from the highly selective and strong interaction between ReO/TcO and Ir(ppy)(bpy), leading to an efficient pre-enrichment of ReO/TcO during analysis and subsequently a much weaker nonradiative decay of the luminescence of Ir(ppy)(bpy), as illustrated by density functional theory (DFT) calculation as well as quantum yield and fluorescence lifetime measurements. Successful quantification of trace ReO in simulated Hanford low-activity waste (LAW) solution containing large excess of Cl, NO, and NO was demonstrated, highlighting the bright future of luminescent PAFs in the area of chemical sensing.
在一系列遗留核设施中，已观察到作为核燃料循环中一种有问题的放射性阴离子的锝酸盐（TcO）在地下水中的污染，这构成了显著的辐射危害和环境问题。因此，开发便捷、快速且灵敏的检测方法对于放射性控制和修复任务至关重要。传统检测方法存在明显缺点，要么受到共存放射性物种的大量干扰（例如放射性计数方法），要么需要大量仪器和分析程序（例如质谱法）。在此，我们首次构建了一种接枝有发光铱（III）有机金属配合物（Ir(ppy)(bpy)；ppy = 2-苯基吡啶，bpy = 2,2-联吡啶）的多孔芳香框架（Ir-PAF），其可用于高效、简便且选择性地检测水溶液中的痕量高铼酸盐/锝酸盐（ReO/TcO）。重要的是，在存在ReO/TcO的情况下，Ir-PAF的发光强度显著增强，从而产生一种检测限为556.9 μg/L的独特开启型传感器。这种卓越的检测能力源于ReO/TcO与Ir(ppy)(bpy)之间高度选择性且强烈的相互作用，导致在分析过程中ReO/TcO的高效预富集，随后Ir(ppy)(bpy)发光的非辐射衰减大大减弱，密度泛函理论（DFT）计算以及量子产率和荧光寿命测量结果证明了这一点。已成功实现对含有大量过量Cl⁻、NO₃⁻和NO₂⁻的模拟汉福德低放废液（LAW）溶液中痕量ReO₄⁻的定量分析，突出了发光多孔芳香框架在化学传感领域的光明前景。
